SNM Annual Meeting Abstracts
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     



J Nucl Med. 2008; 49 (Supplement 1):121P
This Article
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Google Scholar
Right arrow Articles by Kim, J. S.
Right arrow Articles by Lee, D. S.
PubMed
Right arrow Articles by Kim, J. S.
Right arrow Articles by Lee, D. S.

Instrumentation & Data Analysis: Data Analysis & Management

Oncology

Derivation of scan time requirement for maintaining the consistency of PET image quality

Jin Su Kim1, Jae Sung Lee1, Seok-Ki Kim3, Kyeong Min Kim2, Gi Jeong Cheon2 and Dong Soo Lee1

1 Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, South Korea; 2 Division of Nuclear Medicine and RI Application, KIRAMS, Seoul, South Korea; 3 Department of Nuclear Medicine, National Cancer Center, Gyeonggi-do, South Korea

483

Objectives: Image quality of PET for larger patients is relatively poor although injection dose is optimized considering the NECR characteristics of PET scanner. This would be due to the lower level of maximum NECR that can be achieved in these large patients. The aim of this study was to optimize PET scan time for obtaining consistent PET image quality regardless of the body size, based on the relationship between patient specific NECR and body weight (BW).

Methods: Eighty patients (M/F=53/27, BW: 59±10 kg) underwent whole-body FDG PET scans using a Philips GEMINI Dual PET/CT scanner after injection of 0.14 mCi/kg FDG. To derive the relationship between scatter fraction (SF) and BW, we repeatedly performed Monte Carlo simulations using a NEMA scatter phantom the size of which varied according to the relationship between abdominal circumference and BW. Using this information, patient specific NECR was calculated from the prompt and random PET sinograms to obtain the prediction equation of NECR versus BW. Time scaling factor (FTS) for scan duration was finally derived to make the PET images have the equivalent SNR levels.

Results: The SF and NECR had the following nonlinear relationships with BW: SF=0.15xBW0.3 (R2=0.96) and NECR = 421xBW-0.84 (R2=0.71). Derived equation for FTS was 0.01xBW+0.2, which means that, for example, 120-kg person should be scanned 1.8 times longer than a 60-kg person, or the scan time for 40-kg person can be reduced by 30%.

Conclusions: The equation of relative time demand derived in this study will be useful for maintaining the consistency of PET image quality in clinical environments.





This Article
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Google Scholar
Right arrow Articles by Kim, J. S.
Right arrow Articles by Lee, D. S.
PubMed
Right arrow Articles by Kim, J. S.
Right arrow Articles by Lee, D. S.